The name of each kind of seed present in excess of 5 percent shall be shown on the label and need not be accompanied by the word “kind.” When two or more kinds of seed are named on the label, the name of each kind shall be accompanied by the percentage of each. When only one kind of seed is present in excess of 5 percent and no variety name or type designation is shown, the percentage of that kind may be shown as “pure seed” and such percentage shall apply only to seed of the kind named.